Communication apparatus and wireless communication method for semi persistent scheduling

ABSTRACT

Provided are an eNB, a UE and wireless communication methods. The eNB, in an embodiment, includes circuitry operative to fill a SPS activation/deactivation field in a DCI with a predetermined pattern of bits; and a transmitter operative to transmit the DCI to a first UE for the first UE to start periodically transmitting signals to a second UE or stop periodically transmitting signals to the second UE based on the SPS activation/deactivation field. The DCI is in a SPS format formed by adopting part or all bits of at least one field of DCI format 5 as the SPS activation/deactivation field, and information supposed to be transmitted in the at least one field is indicated with the assistance of or by RRC or MAC signaling.

BACKGROUND 1. Technical Field

The present disclosure relates to the field of wireless communication,and in particular, to an eNode B (eNB), a user equipment (UE), andwireless communication methods for semi-static (persistent) scheduling(SPS) activation/deactivation.

2. Description of the Related Art

V2X means communication between vehicles (V2V), communication betweenvehicle and pedestrian (V2P), communication between vehicle andinfrastructure (V2I) or communication between vehicle and network (V2N).It is currently being discussed in 3GPP RAN1, and one starting point tostudy is based on LTE Rel.12/Rel.13 device to device (D2D) framework.

SUMMARY

One non-limiting and exemplary embodiment provides an approach tofacilitate SPS activation/deactivation in V2X or D2D.

In a first general aspect of the present disclosure, there is providedan eNode B (eNB) comprising: circuitry operative to fill a semi-static(persistent) scheduling (SPS) activation/deactivation field in adownlink control information (DCI) with a predetermined pattern of bits;and a transmitter operative to transmit the DCI to a first userequipment (UE) for the first UE to start periodically transmittingsignals to a second UE or stop periodically transmitting signals to thesecond UE based on the SPS activation/deactivation field, wherein theDCI is in a SPS format formed by adopting part or all bits of at leastone field of DCI format 5 as the SPS activation/deactivation field, andinformation supposed to be transmitted in the at least one field isindicated with the assistance of or by radio resource control (RRC) ormedia access control (MAC) signaling.

In a second general aspect of the present disclosure, there is providedan eNode B (eNB) comprising: circuitry operative to scramble cyclicredundancy check (CRC) of a downlink control information (DCI) with aradio network temporary identity (RNTI); and a transmitter operative totransmit the DCI to a first user equipment (UE) for the first UE todetermine whether to transmit a signal to a second UE one time, startperiodically transmitting signals to the second UE or stop periodicallytransmitting signals to the second UE based on only the RNTI, whereinthe DCI is in DCI format 5.

In a third general aspect of the present disclosure, there is providedan eNode B (eNB) comprising: circuitry operative to fill a semi-static(persistent) scheduling (SPS) activation/deactivation field in a firstdownlink control information (DCI) with a predetermined pattern of bits;and a transmitter operative to transmit the first DCI to a first userequipment (UE) for the first UE to transmit a signal to a second UE onetime, start periodically transmitting signals to the second UE or stopperiodically transmitting signals to the second UE based on the SPSactivation/deactivation field, wherein the first DCI is in a formatformed by additionally adding the SPS activation/deactivation field toDCI format 5; the transmitter is also operative to transmit a second DCIto the first UE for the first UE to transmit a signal to the eNB; andthe second DCI is in DCI format 0/1A with all legacy fields beingenabled or in a format formed by additionally adding the same field asthe one added to the DCI format 5 to the DCI format 0/1A, such that thesize of the first DCI is the same as that of the second DCI.

In a fourth general aspect of the present disclosure, there is provideda user equipment (UE) comprising: a receiver operative to receive adownlink control information (DCI) transmitted from an eNode B (eNB); atransmitter operative to start periodically transmitting signals toanother UE or stop periodically transmitting signals to said another UEbased on a SPS activation/deactivation field in the DCI, wherein the DCIis in a SPS format formed by adopting part or all bits of at least onefield of DCI format 5 as the SPS activation/deactivation field, andinformation supposed to be transmitted in the at least one field isindicated with the assistance of or by radio resource control (RRC) ormedia access control (MAC) signaling.

In a fifth general aspect of the present disclosure, there is provided auser equipment (UE) comprising: a receiver operative to receive adownlink control information (DCI) transmitted from an eNode B (eNB);and circuitry operative to determine whether to transmit a signal toanother UE one time, start periodically transmitting signals to saidanother UE or stop periodically transmitting signals to said another UEbased on only the radio network temporary identity (RNTI) scramblingcyclic redundancy check (CRC) of the DCI; wherein the DCI is in DCIformat 5.

In a sixth general aspect of the present disclosure, there is provided auser equipment (UE) comprising: a receiver operative to receive a firstdownlink control information (DCI) transmitted from an eNode B (eNB);and a transmitter operative to transmit a signal to another UE one time,start periodically transmitting signals to said another UE or stopperiodically transmitting signals to said another UE based on a SPSactivation/deactivation field in the first DCI, wherein the first DCI isin a format formed by additionally adding the SPSactivation/deactivation field to DCI format 5; the receiver is alsooperative to receive a second DCI transmitted from the eNB for thetransmitter to transmit a signal to the eNB; and the second DCI is inDCI format 0/1A with all legacy fields being enabled or in a formatformed by additionally adding the same field as the one added to the DCIformat 5 to the DCI format 0/1A, such that the size of the first DCI isthe same as that of the second DCI.

In a seventh general aspect of the present disclosure, there is provideda wireless communication method performed by an eNode B (eNB),comprising: filling a semi-static (persistent) scheduling (SPS)activation/deactivation field in a downlink control information (DCI)with a predetermined pattern of bits; and transmitting the DCI to afirst user equipment (UE) for the first UE to start periodicallytransmitting signals to a second UE or stop periodically transmittingsignals to the second UE based on the SPS activation/deactivation field,wherein the DCI is in a SPS format formed by adopting part or all bitsof at least one field of DCI format 5 as the SPS activation/deactivationfield, and information supposed to be transmitted in the at least onefield is indicated with the assistance of or by radio resource control(RRC) or media access control (MAC) signaling.

In an eighth general aspect of the present disclosure, there is provideda wireless communication method performed by an eNode B (eNB),comprising: scrambling cyclic redundancy check (CRC) of a downlinkcontrol information (DCI) with a radio network temporary identity(RNTI); and transmitting the DCI to a first user equipment (UE) for thefirst UE to determine whether to transmit a signal to a second UE onetime, start periodically transmitting signals to the second UE or stopperiodically transmitting signals to the second UE based on only theRNTI, wherein the DCI is in DCI format 5.

In a ninth general aspect of the present disclosure, there is provided awireless communication method performed by an eNode B (eNB), comprising:filling a semi-static (persistent) scheduling (SPS)activation/deactivation field in a first downlink control information(DCI) with a predetermined pattern of bits; transmitting the first DCIto a first user equipment (UE) for the first UE to transmit a signal toa second UE one time, start periodically transmitting signals to thesecond UE or stop periodically transmitting signals to the second UEbased on the SPS activation/deactivation field, wherein the first DCI isin a format formed by additionally adding the SPSactivation/deactivation field to DCI format 5; and transmitting a secondDCI to the first UE for the first UE to transmit a signal to the eNB,wherein the second DCI is in DCI format 0/1A with all legacy fieldsbeing enabled or in a format formed by additionally adding the samefield as the one added to the DCI format 5 to the DCI format 0/1A, suchthat the size of the first DCI is the same as that of the second DCI.

In a tenth general aspect of the present disclosure, there is provided awireless communication method performed by a user equipment (UE),comprising: receiving a downlink control information (DCI) transmittedfrom an eNode B (eNB); starting periodically transmitting signals toanother UE or stopping periodically transmitting signals to said anotherUE based on a SPS activation/deactivation field in the DCI, wherein theDCI is in a SPS format formed by adopting part or all bits of at leastone field of DCI format 5 as the SPS activation/deactivation field, andinformation supposed to be transmitted in the at least one field isindicated with the assistance of or by radio resource control (RRC) ormedia access control (MAC) signaling.

In an eleventh general aspect of the present disclosure, there isprovided a wireless communication method performed by a user equipment(UE), comprising: receiving a downlink control information (DCI)transmitted from an eNode B (eNB); and determining whether to transmit asignal to another UE one time, start periodically transmitting signalsto said another UE or stop periodically transmitting signals to saidanother UE based on only the radio network temporary identity (RNTI)scrambling cyclic redundancy check (CRC) of the DCI; wherein the DCI isin DCI format 5.

In a twelfth general aspect of the present disclosure, there is provideda wireless communication method performed by a user equipment (UE),comprising: receiving a first downlink control information (DCI)transmitted from an eNode B (eNB); transmitting a signal to another UEone time, starting periodically transmitting signals to said another UEor stopping periodically transmitting signals to said another UE basedon a SPS activation/deactivation field in the first DCI, wherein thefirst DCI is in a format formed by additionally adding the SPSactivation/deactivation field to DCI format 5; and receiving a secondDCI transmitted from the eNB for the transmitter to transmit a signal tothe eNB, wherein the second DCI is in DCI format 0/1A with all legacyfields being enabled or in a format formed by additionally adding thesame field as the one added to the DCI format 5 to the DCI format 0/1A,such that the size of the first DCI is the same as that of the secondDCI.

It should be noted that general or specific embodiments may beimplemented as a system, a method, an integrated circuit, a computerprogram, a storage medium, or any selective combination thereof.

Additional benefits and advantages of the disclosed embodiments willbecome apparent from the specification and drawings. The benefits and/oradvantages may be individually obtained by the various embodiments andfeatures of the specification and drawings, which need not all beprovided in order to obtain one or more of such benefits and/oradvantages.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing and other features of the present disclosure will becomemore fully apparent from the following description and appended claims,taken in conjunction with the accompanying drawings. Understanding thatthese drawings depict only several embodiments in accordance with thedisclosure and are, therefore, not to be considered limiting of itsscope, the disclosure will be described with additional specificity anddetail through use of the accompanying drawings, in which:

FIG. 1 schematically illustrates exemplary SPS transmission in D2D orV2X;

FIG. 2 schematically illustrates a block diagram of an eNB according toan embodiment of the present disclosure;

FIG. 3 illustrates a flowchart of a wireless communication methodperformed by an eNB according to an embodiment of the presentdisclosure;

FIG. 4 schematically illustrates a block diagram of a UE according to anembodiment of the present disclosure;

FIG. 5 illustrates a flowchart of a wireless communication methodperformed by a UE according to an embodiment of the present disclosure;

FIG. 6 illustrates a flowchart of a wireless communication methodperformed by an eNB according to an embodiment of the presentdisclosure;

FIG. 7 illustrates a flowchart of a wireless communication methodperformed by a UE according to an embodiment of the present disclosure;

FIG. 8 illustrates a flowchart of a wireless communication methodperformed by an eNB according to an embodiment of the presentdisclosure; and

FIG. 9 illustrates a flowchart of a wireless communication methodperformed by a UE according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part thereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. It will be readily understood that the aspects ofthe present disclosure can be arranged, substituted, combined, anddesigned in a wide variety of different configurations, all of which areexplicitly contemplated and make part of this disclosure.

In D2D or V2X, one resource allocation mode is based on eNB scheduling.In this mode, an eNB sends a DCI to a transmitting UE for resourceallocation, and the transmitting UE transmits signals to a receiving UEbased on the resource allocation indicated by the DCI. However, the UEdensity in a D2D or V2X group can be high, and thus large signalingoverhead would be caused in the above resource allocation process. Underthis consideration, SPS can be a good resource allocation mechanism tosave control overhead. FIG. 1 schematically illustrates exemplary SPStransmission in D2D or V2X. The eNB first sends SPS activation signalingto the transmitting UE, and then the transmitting UE periodicallytransmits signals to the receiving UE after receiving the SPS activationsignaling. The signals can be transmitted in scheduling assignment (SA)periods, and the signals can comprise both SA and data (as shown inFIG. 1) or only data. If the eNB decides to stop the periodicaltransmission, it sends SPS deactivation signaling to the transmittingUE, and the transmitting UE stops the periodical transmission, that is,not to start next period, when it receives the SPS deactivationsignaling.

In the present disclosure, approaches for SPS activation/deactivation inD2D or V2X are proposed. It is noted that the proposals are applicableto all kinds of D2D or V2X communication. The UE herein refers to anyterminal device suitable for D2D or V2X, for example, a cell phone, apad, any wireless communication device installed in a vehicle, etc., andthe eNB herein refers to any base station suitable for resourceallocation in D2D or V2X.

In an embodiment of the present disclosure, there is provided an eNB 200as shown in FIG. 2 which schematically illustrates a block diagram ofeNB 200 according to an embodiment of the present disclosure. The eNB200 can comprise circuitry 201 which is operative to fill a SPSactivation/deactivation field in a DCI with a predetermined pattern ofbits; and a transmitter 202 which is operative to transmit the DCI to afirst UE for the first UE to start periodically transmitting signals toa second UE or stop periodically transmitting signals to the second UEbased on the SPS activation/deactivation field, wherein the DCI is in aSPS format formed by adopting part or all bits of at least one field ofDCI format 5 as the SPS activation/deactivation field, and informationsupposed to be transmitted in the at least one field is indicated withthe assistance of or by radio resource control (RRC) or media accesscontrol (MAC) signaling.

In the embodiment, the eNB 200 transmits a DCI with a SPSactivation/deactivation field to activate or deactivate the SPStransmission for the first UE (transmitting UE) to the second (receivingUE). Here, the SPS activation/deactivation field is a field forindicating SPS transmission activation or stop SPS transmissiondeactivation, and can be filled with a predetermined pattern of bits,for example, all bits can be filled with “0” or “1”, or some bits arefilled with “0” and the others are filled with “1”. When thetransmitting UE receives the DCI and detects the SPSactivation/deactivation field, the transmitting UE activates SPStransmission or deactivates the SPS transmission that has be startedbased on the SPS activation/deactivation field. For example, when thetransmitting UE detects the SPS activation/deactivation field with allbits being “0”, the transmitting UE activates the SPS transmission to areceiving UE; and when the transmitting UE detects the SPSactivation/deactivation field with all bits being “1”, the transmittingUE deactivates the SPS transmission to the receiving UE.

In the embodiment, the above DCI can be based on DCI format 5 specifiedin 3GPP TS 36.212 with some fields being modified. Specifically, the DCIcan be in a format (referred to as SPS format herein) formed by adoptingpart or all bits of at least one field of DCI format 5 as the SPSactivation/deactivation field, for example, the SPSactivation/deactivation field can have 6 or more bits selected from theDCI format 5. In LTE Rel.12/13, since DCI format 5 and DCI format 0/1Aspecified in 3GPP TS 36.212 are of the same size and share the samesearch space, the above SPS format by reusing some or all bits in DCIformat 5 can have the same size with DCI format 5 and DCI format 0/1Aand thus blind decoding times will not be increased.

The reason why some or even all fields in DCI format 5 can be reused forSPS activation/deactivation is that there is potentially no need for theeNB to dynamically indicate some or even any field from SPS point ofview in D2D or V2X. Therefore, information supposed to be transmitted inthe reused field can be indicated by RRC or MAC signaling or with theassistance of RRC or MAC signaling. For example, since the eNB sends theDCI very infrequently in SPS, quick adaptation on resource allocation(e.g., time resource pattern) is impossible. Therefore, the timeresource pattern can be indicated by RRC or MAC signaling; or the timeresource pattern can be indicated with the assistance of RRC or MACsignaling, for example, the eNB can configure a set of time resourcepatterns via RRC or MAC signaling, and only a few bits in the DCI areused for indicating certain time resource pattern in the configured setfor SPS transmission. In such a way, several bits in the field of “timeresource pattern” in the DCI format 5 can be saved for SPSactivation/deactivation.

In an example, a different radio network temporary identity (RNTI)(referred to as SPS RNTI herein) from the RNTI for the DCI format 5 canbe applied to scramble cyclic redundancy check (CRC) of the DCI in theSPS format in order to facilitate identifying the DCI in the SPS formatand increase the robustness of SPS activation/deactivationidentification. In another example, the RNTI for scrambling CRC of theDCI in the SPS format can be the same as that for scrambling CRC of aDCI in the DCI format 5 when the number of bits for identifying SPSactivation/deactivation in the DCI is large enough to ensure therobustness of SPS activation/deactivation identification, in particularwhen all bits of all fields in the DCI format 5 are adopted as the SPSactivation/deactivation field. As mentioned in the above, in D2D or V2X,there may be no need for the eNB to dynamically indicate any field fromSPS point of view. In view of this, all relevant information on SPS canindicated in RRC or MAC signaling and DCI is only used for SPSactivation/deactivation. In this situation, the SPS RNTI may not beneeded since there are lots of bits used for identifying SPSactivation/deactivation. It is noted that, in a legacy system ratherthan D2D or V2X, some information like “HARQ-ACK resource offset” and“Flag for format0/format1A differentiation” still needs to be indicatedin a DCI as the eNB needs to dynamically control ACK resource as well asDCI format type (0 or 1A).

Tables 1-5 illustrate several examples of the bits in the DCI format 5that are reused for SPS activation/deactivation in V2X or D2D.

TABLE 1 DCI format 5 Special fields for V2X SPS activation Resource forPSCCH All bits are set to “0” TPC command for PSCCH and PSSCH All bitsare set to “0” Frequency hopping flag All bits are set to “0” Resourceblock assignment and hopping All bits are set to “0” resource allocationTime resource pattern All bits are set to “0” Special fields for V2X SPSdeactivation Resource for PSCCH All bits are set to “1” TPC command forPSCCH and PSSCH All bits are set to “1” All bits are set to “1” All bitsare set to “1” Resource block assignment and hopping All bits are set to“1” resource allocation Time resource pattern All bits are set to “1”

Table 1 illustrates that all bits in all fields in DCI format 5 are usedfor SPS activation/deactivation in V2X or D2D. For example, all bitsbeing set to “0” means SPS activation and all bits being set to “1”means SPS deactivation.

TABLE 2 DCI format 5 Special fields for V2X SPS activation Resource forPSCCH N/A TPC command for PSCCH and PSSCH N/A Frequency hopping flag N/AResource block assignment and hopping N/A resource allocation Timeresource pattern MSB 6 bits are set to “000000” Special fields for V2XSPS deactivation Resource for PSCCH N/A TPC command for PSCCH and PSSCHN/A Frequency hopping flag N/A Resource block assignment and hopping N/Aresource allocation Time resource pattern MSB 6 bits are set to “111111”

Table 2 illustrates that most bits (MSB 6 bits) in the “time resourcepattern” field of DCI format 5 are used for SPS activation/deactivationin V2X or D2D.

TABLE 3 DCI format 5 Special fields for V2X SPS activation Resource forPSCCH N/A TPC command for PSCCH and PSSCH Set to “0” Frequency hoppingflag Set to “0” Resource block assignment and hopping N/A resourceallocation Time resource pattern MSB 4 bits are set to “0000” Specialfields for V2X SPS deactivation Resource for PSCCH N/A TPC command forPSCCH and PSSCH Set to “1” Frequency hopping flag Set to “1” Resourceblock assignment and hopping N/A resource allocation Time resourcepattern MSB 4 bits are set to “1111”

Table 3 illustrates that some bits in the “time resource pattern” field,the “TPC command for PSCCH and PSSCH” field and the “Frequency hoppingflag” field are used for SPS activation/deactivation in V2X or D2D.

TABLE 4 DCI format 5 Special fields for V2X SPS activation Resource forPSCCH MSB 3 bits are set to “0” TPC command for PSCCH and PSSCH N/AFrequency hopping flag N/A Resource block assignment and hopping MSB 3bits are set to “0” resource allocation Time resource pattern N/ASpecial fields for V2X SPS deactivation Resource for PSCCH MSB 3 bitsare set to “1” TPC command for PSCCH and PSSCH N/A All bits are set to“1” N/A Resource block assignment and hopping MSB 3 bits are set to “1”resource allocation Time resource pattern N/A

Table 4 illustrates that some bits in the “Resource for PSCCH” field andthe “Resource block assignment and hopping resource allocation” fieldare used for SPS activation/deactivation in V2X or D2D. This example isparticularly applicable to the sub-channel concept mentioned in 3GPPRAN1 (refer to RAN1 contribution R1-156607). When the sub-channelconcept is applied, the “Resource for PSCCH” field and the “Resourceblock assignment and hopping resource allocation” field can besimplified as the basic allocation unit is sub-channel which consists ofmultiple PRBs and PSCCH is located in part of PRBs in each sub-channel.Only part bits in those fields are used for sub-channel indication, andthe others can be used for SPS activation/deactivation in V2X or D2D.

TABLE 5 DCI format 5 Special fields for V2X SPS activation Resource forPSCCH N/A TPC command for PSCCH and PSSCH N/A Frequency hopping flag N/AResource block assignment and hopping N/A resource allocation Timeresource pattern MSB 6 bits are set to “000000” Special fields for V2XSPS deactivation Resource for PSCCH All bits are set to “1” TPC commandfor PSCCH and PSSCH All bits are set to “1” All bits are set to “1” Allbits are set to “1” Resource block assignment and hopping All bits areset to “1” resource allocation Time resource pattern All bits are set to“1”

Table 5 illustrates that activation and deactivation can use differentfields, in particular, MSB 6 bits in the “time resource pattern” fieldare used for SPS activation, and all fields are used for SPSdeactivation.

In addition, as shown in FIG. 2, the eNB 200 according to the presentdisclosure may optionally include a CPU (Central Processing Unit) 210for executing related programs to process various data and controloperations of respective units in the eNB 200, a ROM (Read Only Memory)213 for storing various programs required for performing various processand control by the CPU 210, a RAM (Random Access Memory) 215 for storingintermediate data temporarily produced in the procedure of process andcontrol by the CPU 210, and/or a storage unit 217 for storing variousprograms, data and so on. The above circuitry 201, and transmitter 202,CPU 210, ROM 213, RAM 215 and/or storage unit 217 etc. may beinterconnected via data and/or command bus 220 and transfer signalsbetween one another.

Respective components as described above do not limit the scope of thepresent disclosure. According to one implementation of the disclosure,the functions of the above circuitry 201 and transmitter 202 may beimplemented by hardware, and the above CPU 210, ROM 213, RAM 215 and/orstorage unit 217 may not be necessary. Alternatively, the functions ofthe above circuitry 201 and transmitter 202 may also be implemented byfunctional software in combination with the above CPU 210, ROM 213, RAM215 and/or storage unit 217 etc.

The eNB 200 may also comprise a receiver operative to receive signalsfrom the first UE. In an embodiment, the receiver does not receivesidelink buffer status report (BSR) message or scheduling request (SR)for sidelink from the first UE when the first UE periodically transmitssignals to the second UE, i.e. during SPS transmission.

FIG. 3 illustrates a flowchart of a wireless communication method 300performed by an eNB (e.g. the eNB 200) according to an embodiment of thepresent disclosure. The wireless communication method 300 can comprise astep 301 of filling a SPS activation/deactivation field in a DCI with apredetermined pattern of bits, and a step 302 of transmitting the DCI toa first UE for the first UE to start periodically transmitting signalsto a second UE or stop periodically transmitting signals to the secondUE based on the SPS activation/deactivation field, wherein the DCI is ina SPS format formed by adopting part or all bits of at least one fieldof DCI format 5 as the SPS activation/deactivation field, andinformation supposed to be transmitted in the at least one field isindicated with the assistance of or by RRC or MAC signaling. The detailsand benefits described in the above for eNB 200 can also be applied tothe wireless communication method 300.

Accordingly, embodiments of the present disclosure provide a UE as thetransmitting UE and a wireless communication method performed by thetransmitting UE.

FIG. 4 schematically illustrates a block diagram of a UE 400 as thetransmitting UE according to an embodiment of the present disclosure.The UE 400 can comprise a receiver 401 operative to receive a DCItransmitted from an eNB, and a transmitter 402 operative to startperiodically transmitting signals to another UE (receiving UE) or stopperiodically transmitting signals to said another UE based on a SPSactivation/deactivation field in the DCI, wherein the DCI is in a SPSformat formed by adopting part or all bits of at least one field of DCIformat 5 as the SPS activation/deactivation field, and informationsupposed to be transmitted in the at least one field is indicated withthe assistance of or by RRC or MAC signaling. Optionally, thetransmitter 402 does not transmit sidelink BSR message or SR forsidelink to the eNB when periodically transmitting signals to thereceiving UE.

The UE 400 according to the present disclosure may optionally include aCPU (Central Processing Unit) 410 for executing related programs toprocess various data and control operations of respective units in theUE 400, a ROM (Read Only Memory) 413 for storing various programsrequired for performing various process and control by the CPU 410, aRAM (Random Access Memory) 415 for storing intermediate data temporarilyproduced in the procedure of process and control by the CPU 410, and/ora storage unit 417 for storing various programs, data and so on. Theabove receiver 401, transmitter 402, CPU 410, ROM 413, RAM 415 and/orstorage unit 417 etc. may be interconnected via data and/or command bus420 and transfer signals between one another.

Respective components as described above do not limit the scope of thepresent disclosure. According to one implementation of the disclosure,the functions of the above receiver 401 and transmitter 402 may beimplemented by hardware, and the above CPU 410, ROM 413, RAM 415 and/orstorage unit 417 may not be necessary. Alternatively, the functions ofthe above receiver 401 and transmitter 402 may also be implemented byfunctional software in combination with the above CPU 410, ROM 413, RAM415 and/or storage unit 417 etc.

FIG. 5 illustrates a flowchart of a wireless communication method 500performed by a UE (e.g., the transmitting UE 400) according to anembodiment of the present disclosure. The wireless communication method500 can comprise a step 501 of receiving a DCI transmitted from an eNB,and a step 502 of starting periodically transmitting signals to anotherUE (receiving UE) or stopping periodically transmitting signals to saidanother UE based on a SPS activation/deactivation field in the DCI,wherein the DCI is in a SPS format formed by adopting part or all bitsof at least one field of DCI format 5 as the SPS activation/deactivationfield, and information supposed to be transmitted in the at least onefield is indicated with the assistance of or by RRC or MAC signaling.

It is noted that the details and benefits described in the above for theeNB side can also be applied to the UE side, unless the contextindicates otherwise.

In another embodiment, SPS activation/deactivation can be triggeredpurely by RNTI, and there is no special field used for SPSactivation/deactivation. For example, SPS RNTI 1 is used for SPSactivation, SPS RNTI 2 is used for SPS deactivation, and another RNTI isused for non-SPS transmission (one time transmission). Therefore, the UEreceiving a DCI can determine whether to activate SPS transmission,deactivate SPS transmission or perform one-time transmission based onthe RNTI scrambling the CRC of the DCI.

Accordingly, FIG. 6 illustrates a flowchart of a wireless communicationmethod 600 performed by an eNB according to an embodiment of the presentdisclosure. The wireless communication method 600 can comprise a step601 of scrambling CRC of a DCI with a RNTI, and a step 602 oftransmitting the DCI to a first UE for the first UE to determine whetherto transmit a signal to a second UE one time, start periodicallytransmitting signals to the second UE or stop periodically transmittingsignals to the second UE based on only the RNTI, wherein the DCI is inDCI format 5. In this embodiment, the first UE (transmitting UE) candetermine whether to perform one time transmission, activate SPStransmission or deactivate SPS transmission purely based on the RNTIthat has been used to scramble the CRC of the DCI without modifying theformat of the DCI. Therefore, the same DCI format can be used for SPStransmission and non-SPS transmission.

An embodiment of the present disclosure also provides an eNB forperforming the above method 600, which comprises: circuitry operative toscramble CRC of a DCI with a RNTI; and a transmitter operative totransmit the DCI to a first UE for the first UE to determine whether totransmit a signal to a second UE one time, start periodicallytransmitting signals to the second UE or stop periodically transmittingsignals to the second UE based on only the RNTI, wherein the DCI is inDCI format 5. The block diagram of the eNB in this embodiment can referto the structure shown in FIG. 2.

FIG. 7 illustrates a flowchart of a wireless communication method 700performed by a UE according to an embodiment of the present disclosure.The wireless communication method 700 can comprise a step 701 ofreceiving a DCI transmitted from an eNB, and a step 702 of determiningwhether to transmit a signal to another UE one time, start periodicallytransmitting signals to said another UE or stop periodicallytransmitting signals to said another UE based on only the RNTIscrambling CRC of the DCI, wherein the DCI is in DCI format 5.

An embodiment of the present disclosure also provides a UE forperforming the above method 700, which comprises: a receiver operativeto receive a DCI transmitted from an eNB; and circuitry operative todetermine whether to transmit a signal to another UE one time, startperiodically transmitting signals to said another UE or stopperiodically transmitting signals to said another UE based on only theRNTI scrambling CRC of the DCI, wherein the DCI is in DCI format 5. Theblock diagram of the UE in this embodiment can refer to the structureshown in FIG. 4 except that the transmitter 402 is replaced by the abovecircuitry.

In another embodiment, a new field for SPS activation/deactivation canbe added in DCI format 5; and the DCI format 0/1A is also added with thenew field, or all legacy fields in DCI format 0/1A are automaticallyenabled regardless of FDD/TDD, downlink/uplink, CA/non-CA (carrieraggregation) when V2X or D2D SPS is enabled in order to make the size ofDCI format 0/1A the same as that of the modified DCI format 5, forexample, the “CFI” field (3 bits) regardless of CA or non-CA, the “ULindex” field (2 bits) regardless of FDD or TDD, and the “DownlinkAssignment Index” (2 bits) regardless of FDD or TDD. If the DCI format0/1A size is still not large enough to be aligned with the modified DCIformat 5, padding bits can be added. In this manner, the sizes of theDCI format 0/1A and the DCI format 5 after being modified are still keptthe same, which will not increase the blind decoding times.

Accordingly, FIG. 8 illustrates a flowchart of a wireless communicationmethod 800 performed by an eNB according to an embodiment of the presentdisclosure. The wireless communication method 800 can comprise: a step801 of filling a SPS activation/deactivation field in a first DCI with apredetermined pattern of bits; a step 802 of transmitting the first DCIto a first UE for the first UE to transmit a signal to a second UE onetime, start periodically transmitting signals to the second UE or stopperiodically transmitting signals to the second UE based on the SPSactivation/deactivation field, wherein the first DCI is in a formatformed by additionally adding the SPS activation/deactivation field toDCI format 5; and a step 803 of transmitting a second DCI to the firstUE for the first UE to transmit a signal to the eNB, wherein the secondDCI is in DCI format 0/1A with all legacy fields being enabled or in aformat formed by additionally adding the same field as the one added tothe DCI format 5 to the DCI format 0/1A, such that the size of the firstDCI is the same as that of the second DCI. It is noted that the abovesteps in the method 800 are not necessarily performed in the aboveindicated order. For example, the step 803 can be performed before thesteps 801 and 802.

In the method 800, the first DCI is in a modified DCI format 5 by addinga SPS activation/deactivation field and used for D2D or V2X. The SPSactivation/deactivation field in the modified DCI format 5 indicateswhether the first UE (transmitting UE) should perform a one-timetransmission to the second UE (receiving UE), start SPS transmission tothe second UE or stop the SPS transmission to the second UE. The secondDCI is used for legacy wireless communication (i.e. the communicationbetween the eNB and UEs), and is in a modified DCI format 0/1A by addingthe same field as the SPS activation/deactivation field added to the DCIformat 5, or in the original DCI format 0/1A with all legacy fieldsbeing enabled, such that the first DCI and the second DCI have the samesize.

Table 6 illustrates that a new field used for SPSactivation/deactivation is added in both DCI format 0/1A and DCI format5. In such a manner, DCI format 0/1A still keeps the same size as DCIformat 5.

TABLE 6 DCI format 0 DCI format 1A DCI format 5 Carrier indicatorCarrier indicator Resource for PSCCH Flag for format0/format1A Flag forformat0/format1A TPC command for PSCCH and differentiationdifferentiation PSSCH Hopping flag/RA Type 1 MSB Localized/DistributedVRB Frequency hopping flag assignment flag Resource block assignment andResource block assignment Resource block assignment and hopping resourceallocation hopping resource allocation Modulation and coding schemeModulation and coding scheme Time resource pattern and redundancyversion New data indicator HARQ process number V2X SPSactivation/deactivation TPC command for scheduled New data indicatorPUSCH Cyclic shift for DM RS and OCC Redundancy version index UL indexor Downlink Assignment TPC command for PUCCH Index (DAI) CSI requestDownlink Assignment Index SRS request SRS request Resource allocationtype HARQ-ACK resource offset V2X SPS activation/deactivation V2X SPSactivation/deactivation

Table 7 illustrates that DCI format 0/1A size is maximized by enablingall fields regardless of FDD/TDD, downlink/uplink and CA/non-CA, and anew field is added in DCI format 5. In such a manner, the two DCIs canalso keep the same size so that blind decoding times are not increased.

TABLE 7 DCI format 0 DCI format 1A DCI format 5 Carrier indicatorenabled Carrier indicator enabled Resource for PSCCH Flag forformat0/format1A enabled Flag for enabled TPC command for PSCCHdifferentiation format0/format1A and PSSCH differentiation Hoppingflag/RA Type 1 enabled Localized/Distributed enabled Frequency hoppingflag MSB VRB assignment flag Resource block enabled Resource blockenabled Resource block assignment and hopping assignment assignment andhopping resource allocation resource allocation Modulation and codingenabled Modulation and coding enabled Time resource pattern scheme andredundancy scheme version New data indicator enabled HARQ process numberenabled V2X SPS activation/deactivation TPC command for enabled New dataindicator enabled scheduled PUSCH Cyclic shift for DM RS and enabledRedundancy version enabled OCC index UL index or Downlink enabled TPCcommand for enabled Assignment Index (DAI) PUCCH CSI request enabledDownlink Assignment enabled Index SRS request enabled SRS requestenabled Resource allocation type enabled HARQ-ACK resource enabledoffset

An embodiment of the present disclosure also provides an eNB forperforming the above method 800, which comprises: circuitry operative tofill a SPS activation/deactivation field in a first DCI with apredetermined pattern of bits; and a transmitter operative to transmitthe first DCI to a first UE for the first UE to transmit a signal to asecond UE one time, start periodically transmitting signals to thesecond UE or stop periodically transmitting signals to the second UEbased on the SPS activation/deactivation field, wherein the first DCI isin a format formed by additionally adding the SPSactivation/deactivation field to DCI format 5; the transmitter is alsooperative to transmit a second DCI to the first UE for the first UE totransmit a signal to the eNB; and the second DCI is in DCI format 0/1Awith all legacy fields being enabled or in a format formed byadditionally adding the same field as the one added to the DCI format 5to the DCI format 0/1A, such that the size of the first DCI is the sameas that of the second DCI. The block diagram of the eNB in thisembodiment can refer to the structure shown in FIG. 2.

For the transmitting UE side, FIG. 9 illustrates a flowchart of awireless communication method 900 performed by a UE according to anembodiment of the present disclosure. The wireless communication method900 can comprise: a step 901 of receiving a first DCI transmitted froman eNB; a step 902 of transmitting a signal to another UE one time,starting periodically transmitting signals to said another UE orstopping periodically transmitting signals to said another UE based on aSPS activation/deactivation field in the first DCI, wherein the firstDCI is in a format formed by additionally adding the SPSactivation/deactivation field to DCI format 5; and a step 903 ofreceiving a second DCI transmitted from the eNB for the transmitter totransmit a signal to the eNB, wherein the second DCI is in DCI format0/1A with all legacy fields being enabled or in a format formed byadditionally adding the same field as the one added to the DCI format 5to the DCI format 0/1A, such that the size of the first DCI is the sameas that of the second DCI.

An embodiment of the present disclosure also provides a UE forperforming the above method 900, which comprises: a receiver operativeto receive a first DCI transmitted from an eNB; and a transmitteroperative to transmit a signal to another UE one time, startperiodically transmitting signals to said another UE or stopperiodically transmitting signals to said another UE based on a SPSactivation/deactivation field in the first DCI, wherein the first DCI isin a format formed by additionally adding the SPSactivation/deactivation field to DCI format 5; the receiver is alsooperative to receive a second DCI transmitted from the eNB for thetransmitter to transmit a signal to the eNB; and the second DCI is inDCI format 0/1A with all legacy fields being enabled or in a formatformed by additionally adding the same field as the one added to the DCIformat 5 to the DCI format 0/1A, such that the size of the first DCI isthe same as that of the second DCI. The block diagram of the UE in thisembodiment can refer to the structure shown in FIG. 4.

The present disclosure can be realized by software, hardware, orsoftware in cooperation with hardware. Each functional block used in thedescription of each embodiment described above can be realized by an LSIas an integrated circuit, and each process described in the eachembodiment may be controlled by LSI. They may be individually formed aschips, or one chip may be formed so as to include a part or all of thefunctional blocks. They may include a data input and output coupledthereto. The LSI here may be referred to as an IC, a system LSI, a superLSI, or an ultra LSI depending on a difference in the degree ofintegration. However, the technique of implementing an integratedcircuit is not limited to the LSI and may be realized by using adedicated circuit or a general-purpose processor. In addition, a FPGA(Field Programmable Gate Array) that can be programmed after themanufacture of the LSI or a reconfigurable processor in which theconnections and the settings of circuits cells disposed inside the LSIcan be reconfigured may be used.

It is noted that the present disclosure intends to be variously changedor modified by those skilled in the art based on the descriptionpresented in the specification and known technologies without departingfrom the content and the scope of the present disclosure, and suchchanges and applications fall within the scope that claimed to beprotected. Furthermore, in a range not departing from the content of thedisclosure, the constituent elements of the above-described embodimentsmay be arbitrarily combined.

Embodiments of the present disclosure can at least provide the followingsubject matters.

-   -   1. An eNode B (eNB) comprising:    -   circuitry operative to fill a semi-static scheduling (SPS)        activation/deactivation field in a downlink control        information (DCI) with a predetermined pattern of bits; and    -   a transmitter operative to transmit the DCI to a first user        equipment (UE) for the first UE to start periodically        transmitting signals to a second UE or stop periodically        transmitting signals to the second UE based on the SPS        activation/deactivation field,    -   wherein the DCI is in a SPS format formed by adopting part or        all bits of at least one field of DCI format 5 as the SPS        activation/deactivation field, and information supposed to be        transmitted in the at least one field is indicated with the        assistance of or by radio resource control (RRC) or media access        control (MAC) signaling.    -   2. The eNode B according to 1, wherein    -   all bits of all fields in the DCI format 5 are adopted as the        SPS activation/deactivation field; and    -   the radio network temporary identity (RNTI) for scrambling        cyclic redundancy check (CRC) of the DCI in the SPS format is        the same as that for scrambling CRC of a DCI in the DCI format        5.    -   3. The eNode B according to 1 or 2, further comprising:    -   a receiver operative to receive signals from the first UE,        wherein the receiver does not receive sidelink buffer status        report (BSR) message or scheduling request (SR) for sidelink        from the first UE when the first UE periodically transmits        signals to the second UE.    -   4. An eNode B (eNB) comprising:    -   circuitry operative to scramble cyclic redundancy check (CRC) of        a downlink control information (DCI) with a radio network        temporary identity (RNTI); and    -   a transmitter operative to transmit the DCI to a first user        equipment (UE) for the first UE to determine whether to transmit        a signal to a second UE one time, start periodically        transmitting signals to the second UE or stop periodically        transmitting signals to the second UE based on only the RNTI,    -   wherein the DCI is in DCI format 5.    -   5. An eNode B (eNB) comprising:    -   circuitry operative to fill a semi-static scheduling (SPS)        activation/deactivation field in a first downlink control        information (DCI) with a predetermined pattern of bits; and    -   a transmitter operative to transmit the first DCI to a first        user equipment (UE) for the first UE to transmit a signal to a        second UE one time, start periodically transmitting signals to        the second UE or stop periodically transmitting signals to the        second UE based on the SPS activation/deactivation field,    -   wherein the first DCI is in a format formed by additionally        adding the SPS activation/deactivation field to DCI format 5;    -   the transmitter is also operative to transmit a second DCI to        the first UE for the first UE to transmit a signal to the eNB;        and    -   the second DCI is in DCI format 0/1A with all legacy fields        being enabled or in a format formed by additionally adding the        same field as the one added to the DCI format 5 to the DCI        format 0/1A, such that the size of the first DCI is the same as        that of the second DCI.    -   6. A user equipment (UE) comprising:    -   a receiver operative to receive a downlink control        information (DCI) transmitted from an eNode B (eNB);    -   a transmitter operative to start periodically transmitting        signals to another UE or stop periodically transmitting signals        to said another UE based on a SPS activation/deactivation field        in the DCI,    -   wherein the DCI is in a SPS format formed by adopting part or        all bits of at least one field of DCI format 5 as the SPS        activation/deactivation field, and information supposed to be        transmitted in the at least one field is indicated with the        assistance of or by radio resource control (RRC) or media access        control (MAC) signaling.    -   7. The user equipment according to 6, wherein    -   all bits of all fields in the DCI format 5 are adopted as the        SPS activation/deactivation field; and    -   the radio network temporary identity (RNTI) for scrambling        cyclic redundancy check (CRC) of the DCI in the SPS format is        the same as that for scrambling CRC of a DCI in the DCI format        5.    -   8. The user equipment according to 6 or 7, wherein    -   the transmitter does not transmit sidelink buffer status report        (BSR) message or scheduling request (SR) for sidelink to the eNB        when periodically transmitting signals to said another UE.    -   9. A user equipment (UE) comprising:    -   a receiver operative to receive a downlink control        information (DCI) transmitted from an eNode B (eNB); and    -   circuitry operative to determine whether to transmit a signal to        another UE one time, start periodically transmitting signals to        said another UE or stop periodically transmitting signals to        said another UE based on only the radio network temporary        identity (RNTI) scrambling cyclic redundancy check (CRC) of the        DCI;    -   wherein the DCI is in DCI format 5.    -   10. A user equipment (UE) comprising:    -   a receiver operative to receive a first downlink control        information (DCI) transmitted from an eNode B (eNB); and    -   a transmitter operative to transmit a signal to another UE one        time, start periodically transmitting signals to said another UE        or stop periodically transmitting signals to said another UE        based on a SPS activation/deactivation field in the first DCI,    -   wherein the first DCI is in a format formed by additionally        adding the SPS activation/deactivation field to DCI format 5;    -   the receiver is also operative to receive a second DCI        transmitted from the eNB for the transmitter to transmit a        signal to the eNB; and    -   the second DCI is in DCI format 0/1A with all legacy fields        being enabled or in a format formed by additionally adding the        same field as the one added to the DCI format 5 to the DCI        format 0/1A, such that the size of the first DCI is the same as        that of the second DCI.    -   11. A wireless communication method performed by an eNode B        (eNB), comprising:    -   filling a semi-static scheduling (SPS) activation/deactivation        field in a downlink control information (DCI) with a        predetermined pattern of bits; and    -   transmitting the DCI to a first user equipment (UE) for the        first UE to start periodically transmitting signals to a second        UE or stop periodically transmitting signals to the second UE        based on the SPS activation/deactivation field,    -   wherein the DCI is in a SPS format formed by adopting part or        all bits of at least one field of DCI format 5 as the SPS        activation/deactivation field, and information supposed to be        transmitted in the at least one field is indicated with the        assistance of or by radio resource control (RRC) or media access        control (MAC) signaling.    -   12. The wireless communication method according to 11, wherein    -   all bits of all fields in the DCI format 5 are adopted as the        SPS activation/deactivation field; and    -   the radio network temporary identity (RNTI) for scrambling        cyclic redundancy check (CRC) of the DCI in the SPS format is        the same as that for scrambling CRC of a DCI in the DCI format        5.    -   13. A wireless communication method performed by an eNode B        (eNB), comprising:    -   scrambling cyclic redundancy check (CRC) of a downlink control        information (DCI) with a radio network temporary identity        (RNTI); and    -   transmitting the DCI to a first user equipment (UE) for the        first UE to determine whether to transmit a signal to a second        UE one time, start periodically transmitting signals to the        second UE or stop periodically transmitting signals to the        second UE based on only the RNTI,    -   wherein the DCI is in DCI format 5.    -   14. A wireless communication method performed by an eNode B        (eNB), comprising:    -   filling a semi-static scheduling (SPS) activation/deactivation        field in a first downlink control information (DCI) with a        predetermined pattern of bits;    -   transmitting the first DCI to a first user equipment (UE) for        the first UE to transmit a signal to a second UE one time, start        periodically transmitting signals to the second UE or stop        periodically transmitting signals to the second UE based on the        SPS activation/deactivation field, wherein the first DCI is in a        format formed by additionally adding the SPS        activation/deactivation field to DCI format 5; and    -   transmitting a second DCI to the first UE for the first UE to        transmit a signal to the eNB, wherein the second DCI is in DCI        format 0/1A with all legacy fields being enabled or in a format        formed by additionally adding the same field as the one added to        the DCI format 5 to the DCI format 0/1A, such that the size of        the first DCI is the same as that of the second DCI.    -   15. A wireless communication method performed by a user        equipment (UE), comprising:    -   receiving a downlink control information (DCI) transmitted from        an eNode B (eNB);    -   starting periodically transmitting signals to another UE or        stopping periodically transmitting signals to said another UE        based on a SPS activation/deactivation field in the DCI,    -   wherein the DCI is in a SPS format formed by adopting part or        all bits of at least one field of DCI format 5 as the SPS        activation/deactivation field, and information supposed to be        transmitted in the at least one field is indicated with the        assistance of or by radio resource control (RRC) or media access        control (MAC) signaling.    -   16. The wireless communication method according to 15, wherein    -   all bits of all fields in the DCI format 5 are adopted as the        SPS activation/deactivation field; and    -   the radio network temporary identity (RNTI) for scrambling        cyclic redundancy check (CRC) of the DCI in the SPS format is        the same as that for scrambling CRC of a DCI in the DCI format        5.    -   17. A wireless communication method performed by a user        equipment (UE), comprising:    -   receiving a downlink control information (DCI) transmitted from        an eNode B (eNB); and    -   determining whether to transmit a signal to another UE one time,        start periodically transmitting signals to said another UE or        stop periodically transmitting signals to said another UE based        on only the radio network temporary identity (RNTI) scrambling        cyclic redundancy check (CRC) of the DCI;    -   wherein the DCI is in DCI format 5.    -   18. A wireless communication method performed by a user        equipment (UE), comprising:    -   receiving a first downlink control information (DCI) transmitted        from an eNode B (eNB);    -   transmitting a signal to another UE one time, starting        periodically transmitting signals to said another UE or stopping        periodically transmitting signals to said another UE based on a        SPS activation/deactivation field in the first DCI, wherein the        first DCI is in a format formed by additionally adding the SPS        activation/deactivation field to DCI format 5; and    -   receiving a second DCI transmitted from the eNB for the        transmitter to transmit a signal to the eNB, wherein the second        DCI is in DCI format 0/1A with all legacy fields being enabled        or in a format formed by additionally adding the same field as        the one added to the DCI format 5 to the DCI format 0/1A, such        that the size of the first DCI is the same as that of the second        DCI.

In addition, embodiments of the present disclosure can also provide anintegrated circuit which comprises module(s) for performing the step(s)in the above respective communication methods. Further, embodiments ofthe present can also provide a computer readable storage medium havingstored thereon a computer program containing a program code which, whenexecuted on a computing device, performs the step(s) of the aboverespective communication methods.

The invention claimed is:
 1. A first communication apparatus,comprising: a receiver operative to receive, from a second communicationapparatus, a first downlink control information (DCI), the first DCI isgenerated by adding a new field to fields in a first DCI format, the newfield being an activation or release field used for activation orrelease of Semi Persistent Scheduling (SPS), the fields in the first DCIformat not being used for activation or release of SPS; and atransmitter operative to transmit or terminates semi-persistentlyscheduled data to a third communication apparatus based on the newfield, wherein a second DCI is used for a communication between thefirst communication apparatus and the second communication apparatus,wherein the second DCI, which is transmitted from the secondcommunication apparatus to the first communication apparatus, does notinclude the new field and includes the fields in the first DCI format,and wherein the first DCI and the second DCI are set to have a same sizeby using padding bits.
 2. The first communication apparatus according toclaim 1, wherein the first DCI is used for a SPS communication betweenthe first communication apparatus and the third communication apparatus.3. The first communication apparatus according to claim 1, whereinpadding bits are added to the first DCI when a size of the first DCIformat is less than a size of the second DCL.
 4. The first communicationapparatus according to claim 1, wherein a cyclic redundancy check (CRC)of the first DCI is scrambled with a SPS specific radio networktemporary identity (RNTI) for the first DCI.
 5. The first communicationapparatus according to claim 1, wherein the first DCI includes a timeresource field indicating a time resource from a subset determined by aradio resource control (RRC) signaling.
 6. A first communication methodfor a first communication apparatus, the first communication methodcomprising: receiving, from a second communication apparatus, a firstdownlink control information (DCI), the first DCI is generated by addinga new field to fields in a first DCI format, the new field being anactivation or release field used for activation or release of SemiPersistent Scheduling (SPS), the fields in the first DCI format notbeing used for activation or release of SPS; and transmitting orterminating semi-persistently scheduled data to a third communicationapparatus based on the new field, wherein a second DCI is used for acommunication between the first communication apparatus and the secondcommunication apparatus, wherein the second DCI, which is transmittedfrom the second communication apparatus to the first communicationapparatus, does not include the new field and includes the fields in thefirst DCI format, and wherein the first DCI and the second DCI are setto have a same size by using padding bits.
 7. The first communicationmethod according to claim 6, wherein the first DCI is used for a SPScommunication between the first communication apparatus and the thirdcommunication apparatus.
 8. The first communication method according toclaim 6, wherein padding bits are added to the first DCI when a size ofthe first DCI format is less than a size of the second DCI.
 9. The firstcommunication method according to claim 6, wherein a cyclic redundancycheck (CRC) of the first DCI is scrambled with a SPS specific radionetwork temporary identity (RNTI) for the first DCI format.
 10. Thefirst communication method according to claim 6, wherein the first DCIincludes a time resource field indicating a time resource from a subsetdetermined by a radio resource control (RRC) signaling.
 11. The firstcommunication apparatus according to claim 1, wherein the fields in afirst DCI format are included in the first DCI.
 12. The firstcommunication apparatus according to claim 1, wherein the secondcommunication apparatus is a base station.